The present invention relates to robot arm manipulators for elements and means for aligning objects on the robot arm into a predetermined position.
Robot arms are increasingly being utilized for moving objects from one location to another. In the application of robotics to semiconductor wafer processing as shown in the U.S. patent application Ser. No. 07/051,090, Filed May 15, 1987 commonly assigned herewith, now U.S. Pat. No. 4,897,015 a robot arm is useful for conveying a semiconductor wafer from one location to another through the use of independently controllable radial, circumferential and elevational motions. For many purposes, however, it is important that the wafer transported by the robot arm must be placed in predetermined alignment with respect to its centroid and fiducial.